Lighting device for vehicles

Abstract

The invention relates to a lighting device for vehicles with a first lighting unit (1) comprising a light source (3) and a first planar light guide (4) having a linear light coupling surface (6') and a light coupling surface (6"), and with a second lighting unit (2) comprising a light source (8) and a second planar light guide (9) having a linear light coupling surface (11') and a linear light coupling surface (11"), wherein the first planar light guide (4) and the second planar light guide (9) are integrally connected to form a light guide element, wherein opposite flat sides (5, 5') of the first light guide (4) and opposite flat sides (10,10') of the second optical fiber (9) intersect in a crossing region (13) and wherein the first planar optical fiber (4) has a deflection section (19) between a first planar section (18) and a second planar section (20) of the first planar optical fiber (4), wherein the first planar optical fiber (4) and the second planar optical fiber (9) form a U-shaped light guide element (21) in a transverse plane extending perpendicular to the linear light coupling surface (6', 11') of the first optical fiber (4) and the second optical fiber (9), wherein an extension section (14) of the first optical fiber (4) and an extension section (15) of the second optical fiber (9) project from the crossing region (13) at an angle (μ).

Description

The invention relates to a lighting device for vehicles, having a first light unit containing a light source and a first planar light guide, which has a linear light coupling-in surface and a light decoupling surface, and having a second light unit containing a light source and a second planar light guide, which has a linear light coupling-in surface and a linear light decoupling surface, wherein the first planar light guide and the second planar light guide are integrally connected to one another to form a light guide element, wherein opposite flat sides of the first light guide and opposite flat sides of the second light guide respectively cross one another in a crossing region, and wherein the first planar light guide has a deflection section between a first planar section and a second planar section of the first planar light guide.EP 2 354 637 A2 discloses a lighting device for vehicles, which has a first light unit and a second light unit, each containing a light source and a flat light guide. The planar light guides of the first light unit and of the second light unit are integrally connected to one another and cross one another in a crossing region. The first light unit and the second light unit each have planar light guides which have a light coupling surface on one narrow side, on which the light is coupled and is passed on via opposite flat sides of the respective planar light guides. While the first planar light guide has a deflection section and a first planar section starting from the intersection region, the second planar light guide is planar and extends in one plane. In this way, a linear light decoupling for generating a light function can take place on a side of the second planar light guide opposite the light coupling-in surface. The second light guide has decoupling means, so that light is decoupled on a front flat side of the same in order to generate a light function. Advantageously, a linear light function and a planar light function can thereby be arranged directly next to one another. It is desirable to arrange extended light functions in a space-saving manner.It is therefore an object of the present invention to further develop a lighting device for vehicles with two intersecting flat light guides in such a way that a plurality of light functions can be provided in a space-saving manner.To achieve this object, the invention in conjunction with the preamble of claim 1 is characterized in that the first planar light guide and the second planar light guide form a U-shaped light guide element in a transverse plane running transversely to the linear light coupling surface of the first light guide and of the second light guide, wherein an extension section of the first light guide and an extension section of the second light guide project from the crossing region at an angle.The particular advantage of the invention is that a plurality of light functions can be generated in a space-saving manner. In a front view of the lighting device, only one light emission surface is obtained, which consists of a flat light bundle generated by a first light unit on the one hand and a linear light bundle generated by the second light unit on the other hand. The light emission surface of the emerging flat light bundle is bounded by a deflection section of the first light unit and the intersection region from which the second flat light guide protrudes in the main emission direction. Because a U-shaped light guide element is provided, a width of the planar light decoupling can be defined between the crossing region and the deflection region. The emission of the linear light bundle by the first light unit takes place in the light guiding direction within the planar light guide, so that by forming decoupling means of the first light unit, a defined light flux for the planar and linear light emission of the first light unit can be easily adjusted.According to a preferred embodiment of the invention, the U-shaped light guide element has a relatively large-area apex which is formed by the second section of the first light guide. A first leg is formed by a first portion of the first light guide and a second leg is formed by a first portion of the second light guide. The light emission surface can advantageously be produced in a space-saving manner, wherein the first leg and the second leg can run approximately parallel or at an acute opening angle in a pull-out direction of an injection molding tool.According to a preferred embodiment of the invention, narrow sides are formed as light decoupling surfaces on a side of the extension sections of the first light guide and of the second light guide facing away from the crossing region. Advantageously, two different line-shaped light functions can be generated thereby, which are preferably emitted at right angles. The extension section of the first light guide can serve in particular for generating a side marking light which runs perpendicular to the direction of the light bundle emerging from the second section of the first light guide running in the direction of the vehicle longitudinal axis.According to a further development of the invention, an extension axis of the crossing region runs parallel to an extension of the linear light couplings out at the extension sections of the first light guide and of the second light guide. The axis of extent of the crossing region and the extent of the light coupling-in surfaces run in the vertical direction.According to the invention, the linear coupling-out of light takes place at the extension sections of the first light guide and of the second light guide in the direction of a light guiding direction of the first light guide or of the second light guide. Advantageously, the light yield is relatively high as a result.According to a further development of the invention, at least the second section of the first light guide has decoupling means, so that light is decoupled on a front flat side of the second section in order to generate a predefined light distribution. If appropriate, further second decoupling means can be provided, so that additionally or alternatively the coupled-in light is generated in accordance with a predetermined inscription or for generating a logo on the second section of the first light guide. The illumination surface can thus be used for information purposes.According to a further development of the invention, an inclined surface is provided in the deflection section of the first light guide, by means of which the coupled-in light is deflected by 90°. The inclined surface is preferably planar and arranged at an angle of between 40° and 50°, preferably 45°, to a direction of extension of the first and second sections of the first light guide. Preferably, the inclined surface has reflection optics elements or a mirrored surface.According to a further development of the invention, on a narrow side of the first section of the first light guide and of the second light guide on the light input side, holding arms extend for fastening the U-shaped light guide element to a housing of the lighting device. In this way, a relatively large-surface U-shaped light guide element can be held stably.Further advantages of the invention are evident from the further dependent claims.An exemplary embodiment of the invention is explained in more detail below with reference to the drawings.The following are shown: FIG. 1 shows a perspective illustration of a lighting device according to the invention, and FIG. 2 shows a horizontal section through the illumination device.A lighting device for vehicles according to the invention can serve, for example, in the rear region for generating a tail light function, an outline light function and a side marking light function.The lighting device according to the invention has a first light unit 1 and a second light unit 2, which generate a predefined light distribution independently of one another.The first light unit 1 comprises a number of light sources 3 and a first flat light guide 4, which has two opposing flat sides 5, 5'. The opposing flat sides 5, 5' are connected to one another via a narrow side 6. At a first end of the first light guide 4, a narrow side 6 is formed as a linear light coupling surface. A plurality of light sources 3 are arranged along the light coupling surface 6', so that a first light 7 is coupled into the light coupling surface 6' and is forwarded along the opposite flat sides 5, 5' by total reflection in the direction of a linear light decoupling surface 6'' of the first light guide 4.The second light unit 2 comprises light sources 8 and a second light guide 9 which has opposite flat sides 10, 10' and narrow sides 11 connecting the latter. A narrow side 11' of the second light guide 9 is designed as a linear light coupling surface, along which several light sources 8 are arranged in rows or elongated fashion. The second light 12 emitted by the light sources 8 is coupled into the second light guide 9 by the light coupling surface 11' and totally reflected at the opposite flat sides 10, 10' thereof in the direction of a further narrow side 11 which is designed as a linear light coupling-out surface 11''. At the linear light decoupling surface 11'', the second light 12 is decoupled.The first light guide 4 and the second light guide 9 are formed in one piece and in particular are produced as an injection molded part. In an intersecting region 13, the parallel flat sides 5, 5' of the first light guide 4 intersect with the flat sides 10, 10' of the second light guide 9. Since the intersecting region 13 is arranged in a region of the first light guide 4 and of the second light guide 9, which is adjoined downstream of the luminous flux by only a comparatively short extension section 14 of the first light guide 4 and an extension section 15 of the second light guide 9, the proportion of the light 7, 12 which is lost as a result of scattering in the intersecting other light guide 9 or 4 is relatively small. In particular with respect to the first light guide 4, the extension section 14 has a significantly smaller length l V1 than a length l 1 of a second section 20 of the first light guide 4, which is located upstream of the intersection region 13. The length l V1 of the extension section 14 is less than 50%, preferably less than 30%, in particular less than 10%, of the length l 1 of the second section 20 of the first light guide 4.A length I V2 of the extension section 15 of the second light guide 9 is smaller than a length I 2 of the first section 16 of the second light guide 9, which runs upstream of the intersection region 13.An overall length of the second light guide 9 is the sum of the length l 2 of the first portion 16, the length l V2 of the extension portion 15 and the thickness d 1 of the first light guide 4. Both the extension portion 15 and the first portion 16 of the second light guide 9 are arranged at an angle of 85° to 95°, preferably not at a right angle, with respect to the second portion 20 of the first light guide 4 passing through the intersection region 13 (intersection point), in order to enable extraction from an injection molding tool. The linear light decoupling surface 11'' arranged opposite the linear light coupling-in surface 11' can have scattering optics elements 17 for scattering light decoupling in accordance with a predetermined light distribution.A region of the first light guide 4 arranged upstream of the intersection region 13 has a first planar section 18 which has the light coupling surface 6'. In the direction of the luminous flux, the first section 18 is adjoined by a deflection section 19 at which the coupled-in first light 7 is deflected by approximately 90° in the direction of the second section 20, which is of planar design and extends as far as the intersection region 13. The deflection section 19 has an inclined surface 29 at which the light 7 is deflected. The inclined surface 29 can have reflection optics elements or a mirrored surface.The first section 18, the deflection section 19 and the second section 20 of the first light guide 4 together with the first section 16 of the second light guide 9 form a U-shaped light guide element 21 formed in a plane running transversely to the linear light coupling surface 6', 11' of the first light guide 4 and of the second light guide 9. The crossing region 13 is located in a region of the first light guide 4 and of the second light guide 9 close to the light coupling. The first section 18 and the deflection section 19 of the first light guide 4 form a first leg of the U-shaped light guide element 21, and the first section 16 of the second light guide 9 forms a second leg of the U-shaped light guide element 21.In the crossing region 13, the flat sides 5, 5' of the first light guide 4 or flat sides 10, 10' of the second light guide 9 continue in the same direction, wherein the flat sides 5, 5' or 10, 10' of the first light guide 4 or of the second light guide 9 are alternately interrupted.Preferably, the first light guide 4 and the second light guide 9 have a constant thickness d 1 and d 2 respectively, so that the interruption width of the respective flat sides 5, 5' of the first light guide 4 and flat sides 10, 10' of the second light guide 9 in the crossing region 13 is the same.The flat sides 5, 5' of the first light guide 4 and the flat sides 10, 10' of the second light guide 9 each extend in a straight line toward the intersection region 13 in the luminous flux direction, wherein they enclose an angle φ in the intersection region 13. Since the flat sides 5, 5' and 10, 10' of the first light guide 4 and of the second light guide 9 respectively extend in a straight line, the extension sections 14 of the first light guide 4 and extension sections 15 of the second light guide 9 also enclose the same angle φ with respect to one another. Since in the present exemplary embodiment the flat sides 5, 5' and 10, 10', respectively, of the first light guide 4 and of the second light guide 9 do not converge exactly perpendicularly to one another, the opening angle φ is not 90°, but rather has a deviation of 90° from + / - 5°.An extension axis E K of the intersection region 13 runs parallel to an extension direction of the light coupling surfaces 6', 11' of the first and second light guides 4, 9 or parallel to the light coupling-out surface 6'', 11'' of the extension sections 14, 15.Coupling-out means, not shown, are arranged between the deflection section 19 and the intersection region 13, in which the second section 20 of the first light guide 4 is located, in such a way that the light coupled into the first light guide 4 is coupled out at a front flat side 5' thereof in the main radiation direction H of the illumination device. The coupled-out light 30 can serve, for example, to generate a final light function. For example, elongate prism elements or scattering elements can be arranged as decoupling means on the rear flat side 5 of the second section 20 of the first light guide 4. Alternatively, corresponding decoupling means can also be arranged on the front flat side 5'.Additionally or alternatively, decoupling means can be arranged in the second section 20 of the first light guide 4 in such a way that light 31 exits in the main emission direction H in accordance with a predetermined inscription or logo 22 on the front flat side 5'.If the light beam emitted in the main emission direction H by the second section 20 of the first light guide 4 is intended to have the light function (final light function) and the logo function, the first decoupling means that bring about the light function can lead to a different luminance of the decoupled light than the second decoupling means that are responsible for the logo 22. In the present exemplary embodiment, the first decoupling means are arranged over the entire surface of the second section 20, while the second decoupling means for displaying the logo 22 are arranged only in regions in a part of the second section 20 of the first light guide in which the logo 22 is to be located.To hold the U-shaped light guide element 21, holding arms 23 are arranged as an extension on a narrow side of the first section of the light guide 4 and of the second light guide 9, said narrow side extending toward the light coupling surface, on a side facing the light sources 3, 8. At the ends, the holding arms 23 have fastening lugs 24 for fastening the U-shaped light guide element 21 to a housing of the lighting device, which housing is not shown.The extension section 14 of the first light guide 4 has, on a side facing away from the crossing region 13, the linear light decoupling surface 6", which can be used to generate a side marking light 26. The side marking light 26 is thus emitted substantially perpendicularly to the tail light 30 or the outline light 28 and to the logo illumination 31.The linear light decoupling surface 11'' of the extension section 15 of the second light guide 9, which is arranged on a side facing away from the intersection region 13, can serve for generating an outline light function 28. This light of the contour lamp is irradiated in the same direction (main irradiation direction H) as the tail light 30.Advantageously, the invention makes it possible to produce a plurality of light functions in a compact manner in a space-saving manner.The light sources 3, 8 are preferably designed as LED light sources, which are each arranged on a printed circuit board, not shown. The light sources 3, 8 are arranged in a row.List of reference characters1 1. Light unit 2 2 2 Light unit 3 Light sources 4 1 Light guides 5, 5' Flat sides 6 Narrow sides 6' Light coupling-in surface 6" Light decoupling surface 7 1 Light 8 Light sources 9 2 Light guides 10, 10' Flat sides 11 Narrow sides 11' Light coupling-in surface 11" Light decoupling surface 12 2 Light 13 Intersection region 14 Extension section 15 Extension section 16 1 Section 17 Diffusion optical elements 18 1 Section 19 Deflection section 20 2 Section 21 U-shaped light guide element 22 Logo 23 Holding arm 24 Fastening tabs 25 Light decoupling surface 26 Side marking light 27 Light decoupling surface 28 Contour light function 29 Inclined surface 30 Tail light 31 Logo light function H Main radiation direction E K Extension axis φ Angle l 1, l 2 length l V1, l V2 length d 1, d 2 thicknessReferences included in the specificationThis list of documents cited by the applicant has been produced in an automated manner and is only included for the better information of the reader. The list is not part of the German patent application or utility model application. The DPMA does not take any adhesion for any faults or omissions.Patent Literature citedEP 2 354 637 A2

[0002]

Claims

Lighting device for vehicles, having a first light unit (1) containing a light source (3) and a first planar light guide (4) which has a linear light coupling-in surface (6') and a light decoupling surface (6"), and having a second light unit (2) containing a light source (8) and a second planar light guide (9) which has a linear light coupling-in surface (11') and a linear light decoupling surface (11"), - wherein the first planar light guide (4) and the second planar light guide (9) are integrally connected to one another to form a light guide element, - wherein opposite flat sides (5, 5') of the first light guide (4) and opposite flat sides (10, respectively, 10') of the second light guide (9) cross one another in a crossing region (13), and - wherein the first planar light guide (4) has a deflection section (19) between a first planar section (18) and a second planar section (20) of the first planar light guide (4), characterized in that the first planar light guide (4) and the second planar light guide (9) form a U-shaped light guide element (21) in a transverse plane running transversely to the linear light coupling surface (6', 11') of the first light guide (4) and of the second light guide (9), wherein an extension section (14) of the first light guide (4) and an extension section (15) of the second light guide (9) project from the crossing region (13) at an angle (φ).Lighting device according to claim 1, characterised in that the second section (20) of the first light guide (4) forms an apex of the U-shaped light guide element (21), the first section (18) of the first light guide (4) forms a first leg and the first section (16) of the second light guide (9) forms a second leg of the U-shaped light guide element (21).Lighting device according to claim 1 or 2, characterised in that on a side of the extension sections (14, 15) facing away from the crossing region (13), a narrow side is formed as a linear light decoupling surface (6") of the first light guide (4) and as a linear light decoupling surface (11") of the second light guide (9).Lighting device according to one of Claims 1 to 3, characterized in that the extension sections (14, 15) form an identical angle (φ) with respect to one another as second sections (20) of the first light guide (4) running in the luminous flux direction onto the intersection region (13) and a first section (16) of the second light guide (9).Lighting device according to claim 4, characterised in that the included angle (φ) between the extension sections (14, 15) is 90°.Lighting device according to one of Claims 1 to 5, characterized in that an axis of extent (E K) of the intersection region (13) runs parallel to a direction of extent of the linear light coupling surface (6', 11') of the first light guide (4) and of the second light guide (9).Lighting device according to one of Claims 1 to 6, characterized in that the axis of extent (E K) of the intersection region (13) runs in the vertical direction.Lighting device according to one of Claims 1 to 7, characterized in that the first planar light conductor (4) has output coupling means in the second planar section (20) of the same, in such a way that input light (7) is output coupling out on a flat side (5') of the second planar section (20), which flat side is at the front in the main emission direction (H), in order to generate a predefined light function.Lighting device according to one of Claims 1 to 8, characterized in that the decoupling means are arranged distributed in the second section (20) of the first light guide (4) in such a way that light is decoupled over the full surface from the second section (20) of the first light guide (4) in the main emission direction (H) in order to generate the light function.Lighting device according to one of Claims 1 to 9, characterized in that in the second section (20) of the first planar light guide (4) there are arranged only in regions second decoupling means in such a way that light (31) is decoupled on the front flat side (5') of the first light guide (4) in order to produce an inscription or logo (22).Lighting device according to one of Claims 1 to 10, characterized in that the deflection section (19) of the first light guide (4) has an inclined surface (29), at which the coupled-in light (7) is deflected.Illumination device according to one of Claims 1 to 11, characterized in that the inclined surface (29) is planar or provided with reflection optical elements and runs at an angle in a range from 40° to 50°, preferably at an angle of 45°, to a direction of extent of the first section (18) and of the second section (20) of the first light guide (4).Lighting device according to one of Claims 1 to 12, characterized in that a row of light sources (3, 8) is arranged in each case on the linear light coupling-in surface (6') of the first light guide (4) and on the linear light coupling-in surface (11') of the second light guide (9).Lighting device according to one of Claims 1 to 13, characterized in that a retaining arm (23) is formed on in each case as an extension of a narrow side of the first light guide (4) and of the second light guide (9) which is connected to the light coupling-in surface (6', 11'), for fastening the U-shaped light guide element (21) to a housing of the lighting device.Lighting device according to one of Claims 1 to 14, characterized in that the second section (20) of the first light guide (4) runs substantially perpendicularly to the first section (18) of the first light guide (4) and perpendicularly to the second light guide (9).

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